Electrostatic image developing toner and a method for the production thereof

Abstract

An electrostatic image developing toner comprising polymer particles produced by suspension polymerization of a polymerizable monomer in the presence of an emulsification-preventing agent. Such toners produce images of high image density.

We claim: 
     
       1. An electrostatic image developing toner comprising a colorant, and polymer particles produced by suspension polymerization of a polymerizable monomer in the presence of an emulsification-preventing agent, said particles being from 1 to 50 microns. 
     
     
       2. A method for the production of electrostatic image developing toner comprising a step of forming polymer particles by suspension polymerization of a polymerizable monomer in an aqueous medium in the presence of an emulsification-preventing agent and a colorant, said particles being from 1 to 50 microns. 
     
     
       3. The toner of claim 1 wherein said agent is a nitrite or a mixture of hydrogen peroxide and a molybdate. 
     
     
       4. The toner of claim 1 wherein said agent is a nitrite or mixture of hydrogen peroxide and a bromine compound. 
     
     
       5. The toner of claim 1 wherein said agent is a mixture of a peroxide with iodine or an iodine compound which produces iodine in the presence of said peroxide. 
     
     
       6. The toner of claim 1 wherein said agent is hydrogen peroxide. 
     
     
       7. The toner of claim 1 wherein said agent is a mixture of hydrogen peroxide and a manganese compound which produces divalent manganese ions in the presence of said hydrogen peroxide. 
     
     
       8. The toner of claim 1 wherein said agent is a mixture of hydrogen peroxide with an acid salt which produces divalent magnesium, calcium, or barium ions in the presence of said peroxide. 
     
     
       9. The toner of claim 1 wherein said agent is a compound which produces ferricyanide ions, hypophosphoric ions, or phosphorous acid ions in an aqueous solution. 
     
     
       10. The toner of claim 1 wherein said agent is a mixture of an acid salt of cobalt or nickel with a nitrite or hydrogen peroxide. 
     
     
       11. The toner of claim 1 wherein said agent is a nitrite. 
     
     
       12. The toner of claim 1 wherein said agent is a mixture of at least two of (a) a nitrite   (b) a mixture of hydrogen peroxide and a molybdate   (c) a mixture of hydrogen peroxide and a bromine compound   (d) a mixture of hydrogen peroxide and iodine or an iodine compound which produces iodine in the presence of said hydrogen peroxide.   (e) hydrogen peroxide   (f) a mixture of hydrogen peroxide and a manganese compound which produces divalent manganese ions in the presence of said hydrogen peroxide.   (g) a mixture of hydrogen peroxide and an acid salt which produces divalent magnesium, calcium or barium ions in the presence of said hydrogen peroxide.   (h) a compound which produces ferricyanide ions, hypophosphoric ions, or phosphorous acid ions in an aqueous solution.   (i) a mixture of an acid salt of cobalt or nickel with a nitrite compound or nickel with a nitrite compound or hydrogen peroxide   (j) a nitrite   
     
     
       13. The toner of claim 1 wherein said polymer particles have a molecular weight of 50,000 to 1,000,000. 
     
     
       14. The toner of claim 13 wherein said molecular weight is 50,000 to 200,000. 
     
     
       15. The toner of claim 1 wherein said polymer particles are a bridge structure resulting from polymerization in the presence of a bridging agent. 
     
     
       16. The toner of claim 15 wherein said bridging agent has at least two double bonds. 
     
     
       17. The toner of claim 16 wherein said bridging agent is taken from the class consisting of divinyl compounds and derivatives thereof, diethylene carboxylic acid esters, compounds having at least three vinyl groups, dihydric alcohols, dibasic acids and derivatives thereof, anhydrides of said dibasic acids, esters of said dibasic acids or said anhydrides with lower alcohols, polyhydric alcohols having at least three hydroxy groups, and polyhydric carboxylic acids having at least three hydroxy groups. 
     
     
       18. The toner of claim 17 wherein said bridging agent is taken from the class consisting of divinyl benzene, divinyl naphthalene and derivatives thereof, ethylene-glycol dimethacrylate, diethylene-glycol methacrylate, triethylene-glycol methacrylate, trimethylol-propane triacrylate, acryl methacrylate, t-butyl-aminoethyl methacrylate, tetraethylene-glycol dimethacrylate, 1,3-butane-diol dimethacrylate, N,N-divinyl aniline, divinyl ether, divinyl sulfide, divinyl sulfone, ethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butane diol, neopentyl glycol, 1,4-butene diol, 1,4-bis (hydroxy-methyl) cyclohexane, bis-phenol A, hydrogenated bis-phenol A, polyoxy-ethylenated bis-phenol A, polyoxy-propylenated bisphenol A, maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexane-dicarboxylic acid, succinic acid, adipic acid, sebacic acid, malonic acid, anhydrides of said acids, esters of said acids with lower alcohols, glycerol, trimethylol propane, pentaerythritol, trimellitic acid, and pyromellitic acid. 
     
     
       19. The toner of claim 1 which contains a mold releasing agent which is a polymer of a low molecular weight olefin or a copolymer of an olefinic with non olefinic monomers. 
     
     
       20. The toner of claim 19 wherein said olefin is taken from the class consisting of ethylene, propylene, butene, pentene, hexene, heptene, octene, nonene, decene, 3-methyl butene, 3 methyl pentane, and 3-propyl-5-methyl-hexene. 
     
     
       21. The toner of claim 19 wherein said non olefinic monomers are taken from the class consisting of vinyl ethers, vinyl esters, halo-olefins, acrylic and methacrylic acid esters, acryl derivatives, organic acids, diethyl fumarate, and β-pinene. 
     
     
       22. The toner of claim 1 wherein said agent is taken from the class consisting of molybdic acid salts of alkali metals, ammonium, and magnesium; nitrous acid salts of alkali metals, alkaline earth metals, and antimony; halogenated compounds such as potassium bromide, sodium bromide, potassium iodide, sodium iodide, calcium iodide, and ammonium iodide; manganese compounds such as manganese chloride, manganese nitrate, manganese sulfate, manganese acetate, manganese methacrylate; calcium chloride, magnesium chloride, magnesium sulfate, magnesium acetate, barium chloride, potassium ferricyanate, potassium hypophosphite, sodium hypophosphite, potassium phosphite, hydrochloric acid salts, nitric acid salts and sulfuric acid salts of cobalt and nickel; hexamine cobalt (III) chloride, and ammonium nickel sulfate. 
     
     
       23. The toner of claim 1 wherein a dispersing agent is present. 
     
     
       24. The toner of claim 1 wherein said monomer is taken from the class consisting of ethylenically unsaturated mono olefins, styrenes and derivatives thereof, α-methylene aliphatic monocarboxylic acid esters, acrylic or methacrylic acid derivatives, vinyl ethers, vinyl esters, vinyl ketones, N-vinyl compounds, and vinyl naphthalenes. 
     
     
       25. The toner of claim 24 wherein said monomer is taken from the class consisting of styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-ethyl styrene, 2,4-dimethyl styrene, p-n-butyl styrene, p-tert-butyl styrene, p-n-hexyl styrene, p-n-octyl styrene, p-n-nonyl styrene, p-n-decyl styrene, p-n-dodecyl styrene, p-methoxy styrene, p-phenyl styrene, p-chlorostyrene, 3,4-dichlorostyrene, and the derivatives thereof, ethylene, propylene, butylene, isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethyl-hexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethyl hexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethyl-amino-ethyl methacrylate, diethyl-amino-ethyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, vinyl methyl ether, vinyl ethyl ether, vinyl iso-butyl ether, vinyl-methyl ketone, vinyl-hexyl ketone, vinyl-isopropenyl ketone, N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrolidone, and vinyl naphthalene.